Underlay Behavior EXPLAINED

[dbaldacchino]

Well I'm trying to understand Revit's thinking just for that reason....I want to turn certain underlays on and then use the linework tool to set certain edges to <overhead>. When the underlay is turned off, the linework stays. Now that brings another point....I wish we could specify whether this linework acts as detail lines or model lines, as right now I have to make these changes in ALL plan sheets separately, including the "working" plan views, in order to show overhead items. Sure, I can use model lines and lock them, but I don't like that workflow. I think the the underlay should let the user choose from existing views in the project, thus giving you totla control over HOW the unedrlay looks, and also being able to pick a color/opacity.

[amara]

Furthermore underlays don't print or export. So it seems they are meant to be only for editing purposes. The potential is much more.

[dbaldacchino]

Update:

I heard back from Support about the behavior of underlays.

"There is no cut plane corresponding to the underlay. What you specify is an underlay range and any element which overlaps that range is displayed in its entirety. Setting Level 3 as the underlay results in an underlay range extending from Level 3 to Level 4, which results in the display of the entire roof."

Check the example file I posted....this response is in relation to it. It makes sense now. For example, go to Level 1 and set the underlay to Level 2. The roof will show up in its entirety. That might be confusing, but if you go to an elevation view, you'll see that the roof starts between level 2 and 3, so Revit displays it all. Now give the roof an offset of 3' so it starts exactly on Level 3. Look at the underlay.....the roof doesn't show up anymore.

As to Phasing, the phase is controlled by the view you're in and the Phase Filter settings for the view. So if your view is set to New Construction, your Underlay will display as New Construction with the same Phase Filter settings applied to the view (colors and linetypes for the Underlay change too, but they show in halftone).

[FOUTJM]

for structural framing your underlay will not show if it is on coarse detail level as well. it will have to be on medium or fine.

[tedg]

for structural framing your underlay will not show if it is on coarse detail level as well. it will have to be on medium or fine.

Thanks for this little nugget!
It was the reason I searched for this topic.
I have framing plans (set to course view) where I wanted to show the framing below as an underlay, and for some reason joists show up but W-beams don't?
I suspect it has something to do with how joists are shown in the course view setting vs w-beams.

Now to see if I can force a work around, but this helped to understand the issue.